How do I password-protect a PDF?

Upload the file, set a password and apply. The downloaded copy asks for that password when opened.

What happens if I forget the password?

The file cannot be recovered. Nobody at PDFSolution has a copy of your password, so store it somewhere safe.

How strong is the encryption?

AES encryption is applied to the document. Its real strength depends on your password — a short or common password can be guessed.

Should I email the password with the file?

No. Send the password through a different channel, such as a message or a call.

Can I remove the password later?

Yes, with Unlock PDF, as long as you know the password.

Security

Protect PDF

Adds real AES-256 encryption. Readers will need the password to open the document — keep a copy of it, it cannot be recovered.

This tool runs entirely in your browser. Your document is never uploaded.

Drop a PDF to encrypt

.PDF · up to 50 MB per file · single file

Files are processed in your browser and never uploaded.

How to password-protect a PDF

Add a password to a PDF so it can only be opened by someone who knows it.

1Upload the PDF you want to protect.
2Enter a strong password and confirm it.
3Apply the protection.
4Download the encrypted PDF and share the password separately.

Why use Protect PDF

Adds AES encryption to the document itself.
Useful before emailing payslips, contracts or records.
Works with any standards-compliant PDF reader.
Encryption is applied on your device.

Privacy and how your file is handled

This tool runs in your browser using JavaScript and WebAssembly. The file you choose is read locally by the page and is not uploaded to PDFSolution servers.

Read more in our security overview and privacy policy.

Protect PDF — frequently asked questions

How do I password-protect a PDF?: Upload the file, set a password and apply. The downloaded copy asks for that password when opened.
What happens if I forget the password?: The file cannot be recovered. Nobody at PDFSolution has a copy of your password, so store it somewhere safe.
How strong is the encryption?: AES encryption is applied to the document. Its real strength depends on your password — a short or common password can be guessed.
Should I email the password with the file?: No. Send the password through a different channel, such as a message or a call.
Can I remove the password later?: Yes, with Unlock PDF, as long as you know the password.

Related PDF tools

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